Perry’s new release becomes her fourth No. 1 on the ARIA Singles Chart following “I Kissed A Girl” (Aug. 2008), “California Gurls” (June 2010) and “Roar” (Aug. 2013) and it’s her first new entry on the chart since “This Is How We Do” reached No. 18 in Sept. 2014.

Melbourne rapper Illy lands his first top 10 single with "Papercuts" (Warner Music) featuring Vera Blue, which rises 37-8 to eclipse his previous best of No. 18 with "Tightrope" from June 2014.

The week’s other best debut comes from homegrown pop-punk band 5 Seconds Of Summer, whose "Girls Talk Boys" (Capitol/EMI) from the new Ghostbusters soundtrack appears at No. 21. It’s the Sydney group’s 10th top 50 single in Australia.

Meanwhile, Good Charlotte leads the national albums chart with Youth Authority, their first release in six years. Youth Authority opens at the ARIA Albums Chart summit to give the U.S. pop-punk act their second No. 1 on these shores after The Chronicles Of Life And Death, which reached the top in October 2004, and their first No. 1 as an independent artist (it’s released through the Madden Brothers’ label MDDN and distributed worldwide by Kobalt Label Services). The twins, who have high profiles Down Under thanks to their stints as coaches on the local production of The Voice, scored No. 1s with their 2014 Madden Brothers album Greetings From California and single "We Are Done".